Mechanical riveting machine



April 14, 1936. A A, NQRIN ET AL 2,037,476

MECHANICAL RIVETi NG MACHINE Original Filed Oct. 7, 1932 2 Sheets-Sheet l INVENTURS AME?! UZ 5077 AZZan A. Nmru ATTORNEY.

April 1935- A. A. NORIN ET AL 2,037,476

MECHANICAL RIVETING MACHINE Original Filed 001;. '7, 1952 2.Sheets-Sheet 2 INVENTCIRS Allan A. Nurm BY l//// AZbsrf/Z'Uiaazz Patented Apr. 14, 1936 PATENT OFFICE DHZCHANICAL RIVETING MACHINE Allan A. Norin and Albert M. Olson, Chicago, Ill.,

assignors to Norin Engineering Company, Chicago, Ill. Application October 7, 1932, Serial No. 636,661

Renewed April 14, 1934 6 Claims. (01. 78-39) This invention appertains to power presses and more particularly to novel means for operating the ram from a crank shaft or power driven eccentric. 7

One of the primary objects of our present invention is to provide a simple, economical and eificient punch press with a system of compound levers for transmitting power and motion from a fly-wheel to the ram in such a way that the stroke of the ram through part of the total length of the stroke moves with a uniform speed and that the speed of the ram is in relationship to the positions of links and levers between the crank shaft and ram. 7

Another salient object of our invention is to provide a punch press with means for automatically releasing the ram at predetermined tonnage at any part of the ram stroke so that when a predetermined load is inserted between the ram and the platen of the press, the ram will give regardless of the position thereof.

A further object of our invention is to provide a novel arrangement for adjusting the tonnage from no load up to the capacity for which the press is designed, the arrangement being such that the frame as well as other parts composing the press cannot be overloaded.

. A still further object of our invention is to provide a punch press embodying the above characteristics, in which means is provided whereby the crank shaft can be rotated around one complete revolution. for obtaining one cycle of ram movement irrespective of the position at which the ram is released.

With these and other objects in view, the invention consists in the novel construction, arrangement and formation of parts, as will be hereinafter more specifically described, claimed and illustrated in the accompanying drawings, in which:

Figure 1 is a front elevation of a punch press embodying my invention.

Figure 2 is a fragmentary side elevation of the press with parts thereof broken away and in section to illustrate structural detail, the ram being shown in its lowered position, the releasing position of the various links and leversbeing shown in dotted lines.

Figure 3'is a view similar to Figure 2 showing the ram in its raised position.

Figure 4 is a horizontal sectional view taken on the line 4-4 of Figure 3 looking in the direction of the arrows.

Referring to the drawings in detail, wherein similar reference characters designate the corresponding parts throughout the several views, the letter A generally indicates a punch press embodying any preferred type of supporting frame I0.

Journalled in the front upper portion of the 5 frame I is a transversely extending drive shaft 1 l. The frame I0 can be provided with any preferred type of bearings I2 for rotatably supporting this shaft. Slidably mounted on the frame below the shaft II is the ram I3. This ram is 1 mounted for movement toward and away from the plattenl l. Any preferred type of guides can be provided for the ram and as shown, jibs are employed for holding the ram in place. The jibs [5 are provided with adjusting screws l6 and clamping screws I! for holding the same in proper position.

The ram I3 can be provided with a clamp l8 and screws IQ for holding dies, etc. to the ram and a slot 2|] is formed in the ram above the clamp for the reception of a knock-out bar, as is usual in press constructions.

As pointed out in the objects, the salient feature of my present invention is the simple and novel drive utilized between the shaft II and the ram [3 with the means for releasing the ram at any predetermined pressure or load. This shaft II can be considered as a crank or cam shaft and in the present instance, the same is provided with an eccentric 2| arranged between the arms 22 of the frame.

Mounted on the eccentric 2| is a triangularlyshaped operating head 23 which forms a crank lever for actuating the ram. This crank lever 23 is connected at one side by means of links 24 with the upper end f the ram. As shown, pivot pins 25 and 26 are employed respectively for connecting the links with the crank lever and with the upper end of the ram. The lever and the links 24 formsubstantially a toggle, for a purpose which will be later set forth. The crank lever is guided movably by links 21, which are pivotally connected to the crank lever by means of pivot pins 28 to the opposite side of the lever from the links 24. The links 21 are in turn connected by means of a pivot pin 29 with links 30 which are rockably mounted on their lower ends on a stationarypivot pin 3| carried by the frame It. Pin 29 is normally held stationary by links 32 and 33 which are pivotally connected together by means of a pivot pin 34. The front link 32 is mounted upon the pivot pin 29, while the rear end of the link 33 is rockably mounted upon the pin 35 carried by the rear end of the frame In. By referring to Figures 2 and 3, it can be seen that the links 2? and 30 form a toggle connection, while the links 32 and 33 form a toggle connection.

Arranged above the links 32 and 33 is a novel spring device, which includes a cylinder 36. This cylinder 36 has slidably mounted therein a plunger or a spring retainer 31 and a relatively heavy coil spring 38 is arranged within the cylinder between the plunger 31 and the bottom wall of the cylinder. The plunger 3! has pivotally connected thereto by means of a pin 39 an adjusting screw 48, which extends through a cross bar 4i secured to the arms 22 of the frame. Adjusting nuts 42 and 43 are provided for the screw 40' so that the position of the plunger 3'! can be regulated within the cylinder for creating the desired tension on the compression spring 38. A lock nut 4-4 is provided for holding the adjusting nut 42 in position and if desired, a lock screw 45 can be threaded into the .cross bar for engaging the screw 40 to hold the same against turning movement. The extreme lower end of the cylinder is provided with ears 46 which are pivotally connected to the pivot pin 34.

A set screw 47 is carried by the frame for adjusting levers 32 and 33 and this screw is located directly below the cylinder 38.

The crank or cam shaft II can be driven in any preferred manner, but as in the usual constr'uction of presses, we preferably mount rotatably on the shaft H a fly-wheel 48. A clutch 49 is provided for connecting the fly-wheel with the shaft H at the desired time and this clutch 49 can be operated from a suitable foot treadle if desired. Likewise, the shaft I I can be provided with a brake 50 if desired.

In operation of our device, assuming that the fly-wheel 48 is pulled by a belt from a line shaft or connected to a motor by V belts, the energy from the power supply is stored in the fly-wheel. Connecting the fly-wheel with the crank shaft II by means of the clutch 49 puts the crank shaft into rotary motion, whereby crank lever 23 is moved downward by the throw of the eccentric 2| and the predetermined motion is given ram l3 through guide links 21 and lower toggle link 24. Spring 38 acts in one direction against the cross bar 4| and in the other direction against the pin 34 and the stop screw 47. Links 32, 33 and 30 determine the position of the pin 29. Pin 29 holds the guide link 27 in position until the load between the ram I3 and platten I4 is reached through lower toggle link 24, crank eccentric 2| and guide link 21 and when that reaction becomes stronger than spring 38, resisting through levers 33, 38 and 32, then the ram l3 stops, but the crank shaft H continues its rotation. The toggle link 24 then becomes a guide link, while links 30, 32 and 33 are moved from their original position compressing spring 38, as shown in dotted lines in Figure 2 of the drawings. Immediately, the ram comes to a standstill and the angularity of the links lessens the load between the ram and frame.

It can be seen by referring. to Figure 2 that in eifect the toggle formed by the links 21 and 30 breaks allowing the breaking of the toggle formed by the crank lever 23 and links 24.

The construction is such that the ram can be released at any point during its travel without interfering with the rotation of the crank shaft. By adjusting the spring 38, the ram can be caused to stop at any predetermined load.

As the crank shaft continues revolving after the stopping of the ram, the crank lever is again brought to position where the ram stopped and the levers 32, 33 and 33 are brought to their original position and then the ram is carried back to its starting point.

From the foregoing description, it can be seen that the load is perfectly controlled which differs entirely from ordinary crank presses.

Changes in details may be made without departing from the spirit or the scope of this invention, but what we claim as new is:

1. In a press, a frame, a shaft rotatably mounted in the frame, means for continuously rotating the shaft in one direction during one complete cycle, an eccentric on the shaft, a crank lever mounted on the eccentric having pivot pins on the opposite sides of the eccentric, a ram slidably mounted on the frame, links pivotally connecting the ram to the pin on one side of the crank lever, guide links pivotally connected to the pin on the other side of the crank lever, a toggle including a pair of pivotally connected links pivotally connected to the frame and to the guide links, a supporting link pivotally connected to the frame and to the guide link at the point of connection of the toggle therewith, and a spring tension device bearing on the toggle at its pivot point.

2. In a press, a frame, a shaft rotatably mounted in the frame, means for continuously rotating the shaft in one direction during one complete cycle, an eccentric on the shaft, a crank lever mounted on the eccentric having pivot pins on the opposite sides of the eccentric, a ram slidably mounted on the frame, links pivotally connecting the ram to the pin on one side of the crank lever, guide links pivotally connected to the pin on the other side of the crank lever, a toggle including a pair of pivotally connected links pivotally connected to the frame and to the guide links, a supporting link pivotally connected to the frame and to the guide link at the point of connection of the toggle therewith, and a spring tension device bearing on the toggle at its pivot point, and means for adjusting said spring tension means.

3. In a press, a frame, a shaft rotatably mounted in the frame, means for continuously rotating the shaft in one direction during one complete cycle, an eccentric on the shaft, a crank lever mounted on the eccentric having pivot pins on the opposite sides of the eccentric, a ram slidably mounted on the frame, links pivotally connecting the ram to the pin on one side of the crank lever, guide links pivotally connected to the pin on the other side of the crank lever, a toggle including a pair of pivotally connected links pivotally connected to the frame and to the guide links, a supporting link pivotally connected to the frame and to the guide link at the point of connection of the toggle therewith, a spring tension device bearing on the toggle at its pivot point, means for adjusting said spring tension means, and adjustable means for limiting downward movement of the toggle.

4. In a press, a frame, a drive shaft rotatably mounted on the frame, means for continuously rotating the shaft in one direction during one cycle, an eccentric on the shaft, a crank lever on the eccentric having pivot pins on opposite sides of the eccentric, a ram slidably mounted on the frame, links connecting the ram with one of the pivot pins of the crank lever, a guide link pivotally connected to the other pivot pin of the crank lever, a toggle pivotally connected to the guide link and to the frame, a supporting link pivotally connected to the frame and to the guide link at the point of connection of the toggle therewith, and means for permitting the breaking of the toggle at predetermined tonnage.

5. In a press, a frame, a shaft rotatably mounted in the frame, means for continuously rotating the shaft in one direction during one cycle, a crank lever on the shaft having a pair of pivot pins arranged on opposite sides of the shaft, a ram slidably mounted on the frame, a link pivotally connecting the ram to one of the pivot pins, a guide link pivotally connected to the other pivot pin, a toggle pivotally connected to the frame and to the guide link, a supporting link pivotally connected to the frame and to the guide link at the point of connection of the toggle therewith, a spring normally bearing against the toggle, and means for adjusting the tension of said spring.

6. In a press, a frame, a shaft rotatably mounted in the frame, means for continuously rotating the shaft in one direction during one cycle, a crank lever on the shaft having a pair of pivot pins arranged on opposite sides of the shaft, a ram slidably mounted on the frame, a link pivotally connecting the ram to one of the pivot pins, a guide link pivotally connected to the other pivot pin, a toggle pivotally connected to the frame and to the guide links, a supporting link pivotally connected to the frame and to the guide link at the point of connection of the toggle therewith, a spring normally bearing against the toggle, means for adjusting the tension of said spring, and adjustable stop means resisting movement of the toggle under influence of said spring.

ALLAN A. NORIN. ALBERT M. OLSON. 

